[backport] Chat: Use Ctrl-A for 'select all' again (instead of Ctrl-B) Backport of 783959a6810b to branch ui-scaling by sheepluva

void fpcrtl_halt(int num) {
    __coverity_panic__();
}

int fpcrtl_abs(int num) {
    return num >= 0 ? num : -num;
}